Bi-directional fixating/locking transvertebral body screw/intervertebral cage stand-alone constructs having a central screw locking lever, and pliers and devices for spinal fusion

Abstract

A bi-directional fixating transvertebral (BDFT) screw/cage apparatus including an intervertebral cage for maintaining disc height, and a method of inserting the same is provided. The intervertebral cage includes a first internal screw guide and a second internal screw guide, a first screw member and a second screw member, and a central screw locking lever coupled to the intervertebral cage, wherein the central screw locking lever prevents the first screw member and the second screw from pulling-out of the first internal screw guide and the second internal screw guide. The central screw locking lever includes a rotatable handle and stem portion, or a screw locking horizontal bracket. A pliers device for inserting and removing the bi-directional fixating transvertebral (BDFT) screw/cage apparatus, a posterior cervical and lumbar facet joint staple, and a staple gun for a posterior cervical and lumbar facet joint staple also are provided.

What is claimed is: 
     
       1. A bi-directional fixating transvertebral (BDFT) screw/cage apparatus, comprising:
 an intervertebral cage for maintaining disc height, the intervertebral cage including a first internal screw guide and a second internal screw guide; 
 a first screw member and a second screw member, each of the first screw member and the second screw member having a screw head at a first end, a tapered end at a second end, and a threaded body disposed within the intervertebral cage, the screw head including a recess; 
 wherein each of the first internal screw guide and the second internal screw guide are angled to orient the first screw member and the second screw member bi-directionally in opposite directions; and 
 a central screw locking lever coupled to the intervertebral cage, wherein the central screw locking lever includes a first projection and a second projection that respectively engage the recess in the screw head of each of the first screw member and the second screw member and prevent the first screw member and the second screw member from pulling-out of the first internal screw guide and the second internal screw guide. 
 
     
     
       2. The apparatus according to  claim 1 , wherein the central screw locking lever is rotatably coupled to the intervertebral cage. 
     
     
       3. The apparatus according to  claim 2 , wherein the central screw locking lever includes:
 a handle portion; and 
 a stem portion extending from a lower side of the handle portion, the stem portion being substantially perpendicular to the lower side of the handle portion. 
 
     
     
       4. The apparatus according to  claim 3 , wherein the central screw locking lever is rotatable about an axis of the stem portion. 
     
     
       5. The apparatus according to  claim 3 , wherein the first internal screw guide and the second internal screw guide are aligned along a longitudinal axis of the intervertebral cage, and wherein the central screw locking lever is rotatable between:
 an unlocked position in which the handle portion is transverse to the longitudinal axis of the intervertebral cage, and 
 a locked position in which the handle portion extends along the longitudinal axis of the intervertebral cage. 
 
     
     
       6. The apparatus according to  claim 5 ,
 wherein the first screw member and the second screw member are exposed when the handle portion is in the unlocked position, and 
 wherein the handle portion of the central screw locking lever covers and locks the first screw member and the second screw member in the intervertebral cage when the handle portion is in the locked position. 
 
     
     
       7. The apparatus according to  claim 2 , wherein the central screw locking lever is a T-shaped screw locking lever, and
 wherein the T-shaped screw locking lever includes the first projection and the second projection, 
 each of the first projection and the second projection including a semi-spherical portion that engages the recess in the screw head of each of the first screw member and the second screw member to prevent the first screw member and the second screw member from pulling-out of the first internal screw guide and the second internal screw guide. 
 
     
     
       8. The apparatus according to  claim 2 , wherein a top face of the intervertebral cage includes an opening for engaging the central screw locking member. 
     
     
       9. The apparatus according to  claim 8 , wherein the opening is formed between the first internal screw guide and the second internal screw guide. 
     
     
       10. The apparatus according to  claim 8 , wherein the central screw locking lever includes a first threaded portion and the opening includes a corresponding second threaded portion, and
 wherein the central screw locking lever is threaded into the opening of the intervertebral cage by engaging the first threaded portion of the central screw locking lever with the second threaded portion of the opening. 
 
     
     
       11. The apparatus according to  claim 9 , wherein the central screw locking lever is press-fit into the opening of the intervertebral cage. 
     
     
       12. A pliers device for inserting and removing the apparatus according to  claim 1 , wherein the pliers device comprises:
 a first arm rotatably coupled to a second arm; 
 wherein each of the first arm and the second arm includes a handle portion on a first end; 
 wherein the first arm includes an upper plier tip and the second arm includes a lower plier tip, and 
 wherein the first arm and the second arm engage the central screw locking lever. 
 
     
     
       13. The pliers device according to  claim 12 , wherein the upper plier tip and the lower plier tip each include a stop configured to engage the bracket flexion grips. 
     
     
       14. The pliers device according to  claim 12 , comprising:
 a leaf spring between the first arm and the second arm, wherein the leaf spring biases the first handle portion away from the second handle portion. 
 
     
     
       15. A method of inserting a bi-directional fixating transvertebral (BDFT) screw/cage apparatus between a first vertebral body and a second vertebral body, the method including:
 inserting an intervertebral cage into a midline of a disc space between the first vertebral body and the second vertebral body until the intervertebral cage is one of flush and countersunk relative to the first vertebral body and the second vertebral body; 
 inserting a first screw member into a first internal screw guide of the selected intervertebral cage; 
 inserting a second screw member into a second internal screw guide of the selected intervertebral cage; 
 screwing the first screw member and the second screw member into the first vertebral body and the second vertebral body respectively; and 
 locking the first screw member and the second screw member in the intervertebral cage using a central screw locking lever coupled to the intervertebral cage, wherein the central screw locking lever includes a first projection and a second projection that respectively engage a recess in a screw head of each of the first screw member and the second screw member and prevent the first screw member and the second screw from pulling-out of the first internal screw guide and the second internal screw guide. 
 
     
     
       16. The method according to  claim 15 , wherein the central screw locking lever is rotatably coupled to the intervertebral cage, and
 wherein said locking the first screw member and the second screw member in the intervertebral cage includes rotating the central screw locking lever with respect to the intervertebral cage from an unlocked position in which the first screw member and the second screw member are exposed to a locked position in which the central screw locking lever covers and locks the first screw member and the second screw member in the intervertebral cage. 
 
     
     
       17. The method according to  claim 16 , further comprising:
 unlocking the first screw member and the second screw member, 
 wherein said unlocking includes:
 rotating the central screw locking lever with respect to the intervertebral cage from the locked position in which the central screw locking lever covers and locks the first screw member and the second screw member in the intervertebral cage to the unlocked position in which the first screw member and the second screw member are exposed. 
 
 
     
     
       18. The method of  claim 15 , wherein the central screw locking lever includes a handle portion; and a stem portion extending from a lower side of the handle portion, the stem portion being substantially perpendicular to the lower side of the handle portion. 
     
     
       19. The method of  claim 18 , wherein the central screw locking lever is rotatable about an axis of the stem portion. 
     
     
       20. The method of  claim 18 , wherein the first internal screw guide and the second internal screw guide are aligned along a longitudinal axis of the intervertebral cage, and the method further comprises:
 rotating the central screw locking lever between: 
 an unlocked position in which the handle portion is transverse to the longitudinal axis of the intervertebral cage, and 
 a locked position in which the handle portion extends along the longitudinal axis of the intervertebral cage. 
 
     
     
       21. The method of  claim 20 , wherein the first screw member and the second screw member are exposed when the handle portion is in the unlocked position, and
 wherein the handle portion of the central screw locking lever covers and locks the first screw member and the second screw member in the intervertebral cage when the handle portion is in the locked position. 
 
     
     
       22. The method of  claim 18 , wherein the central screw locking lever is a T-shaped screw locking lever, and wherein the T-Shaped screw locking lever includes the first projection and the second projection , each of the first projection and the second projection including a semi-spherical portion,
 the method further comprising: 
 Engaging the semi-spherical portion of each of the first projection and the second projection with the recess in the screw head of each of the first screw member and the second screw member to prevent the first screw member and the second screw member from pulling-out of the first internal screw guide and the second internal screw guide. 
 
     
     
       23. The method of  claim 18 , wherein a top face of the intervertebral cage includes an opening for engaging the central screw locking member. 
     
     
       24. The method of  claim 23 , wherein the opening is formed between the first internal screw guide and the second internal screw guide. 
     
     
       25. The method of clam  23 , wherein the central screw locking lever includes a first threaded portion and the opening includes a corresponding second threaded portion, and
 the method further comprising: 
 threading the central screw locking lever into the opening of the intervertebral cage by engaging the first threaded portion of the central screw locking lever with the second threaded portion of the opening. 
 
     
     
       26. The method of  claim 24 , wherein the central screw locking lever is press-fit into the opening of the intervertebral cage.